The fire, which broke out in the roof of the Brown Pub in Methven on Tuesday morning, was likely caused by timbers or bird nest/detritus against the chimney.
It then spread throughout the roof space above the accommodation, says Fire and Emergency New Zealand fire risk management officer Bevan Findlay.
“The fire started in the roof space at the top of the brick part of that chimney, at the point where it transitioned from the brick chimney to the metal flue (i.e. at ceiling level). The other two chimneys in the building were replaced after the Christchurch earthquake damaged the southern half of the building, but the chimney involved in the fire has been there longer than the current owner (i.e. more than 19 years).
Mr Findlay said everything below the ceiling was undamaged by the fire, but there was water damage, as a lot of water was used to extinguish the fire.
“Locals will be glad to know that the pub part of the building was undamaged,” he said.
Mr Findlay said it was an example of the need to have chimneys maintained, and why there were stricter rules for new chimneys around safety and containing heat to the chimney. Older installations like this will not have been built to current building standards, so can be unsafe – even when they have been seemingly fine for a long time.”